Air-brake-control device



' 1,640,480 1927' T. F. CLARK ET AL AIR BRAKE CONTROL DEVICE Filed June 24. 1925 3 Shets-Sheet l M ATT RNEY T. CLARK ET AL AIR BRAKE CONTROL DEVICE 3 Sheets-Sheet 2 Filed June 24. 1925 iNVENTORS ATTORNEY l 1,640,480 1927' T. E. CLARK ET AL AIR BRAKE CONTROL DEVICE Filed June 24. 1925 3 Sheets-Sheet 3 mmxw w ATTORNEY Patented Aug. 30, 1927.

warren srATEs PATENT OFFICE. 1

THOMAS E. CLARK AND CHARLES'B. STONE, OF DETROIT, MICHIGAN, ASSIGN-ORS 1T0 CONTINUOUS TRAIN CONTROL .CORPORATIGN, OF' DETROIT, MICHIGANfA COR- PonA'rIoN or MICHIGAN.

AIRERAKE-CONTROL DEVICE.

Application filed June 24, 1925. Serial No. 39,214..

to be stopped in a block 'whenthe signal light at the exit end thereof indicates that the next or, second block in advance is occupied.

This invention consists of instrumentalities on a locomotive embodying a collector Ill) coil and a resonant circuit therefor tuned to the wave length of current propagated in the track rails by a transmitter of high-frequency oscillating currents, a current source and an electric brake-controlling valve mechanism normally energized thereby, and means whereby the circuit between the current source and the valve mechanism may beinterrupted whenever current is generated in said coil circuit because of the current propagated in the rails, incombination with pneumatically operated means for normally preventing the escape oi the train line pressure of the air brake system, the conduit for the air under pressure connecting to said pneumatically operated means being interrupted by said valve mechanism when deenergized so as to permit the escape of air from the train line pipe.

It further consists of the details of construct-ion illustrating the accompanying drawings and particularly pointed out in the claims.

In the drawings, Fig. 1 is a diagram of two signal and control stations adapted to propagate high-frequency oscillating currents in the rails of a track. Figs. 2 and '3 are diagrams of the wirings of instrumen' talities mounted on a locomotive and vertical sections of the pneumatically operated means for releasing the air pressure in the train line pipe, he two figures showing the parts in their normal and pressure-releasing positions respectively. Fig. 4t is a diagram of a current transmitting mechanism.

Similar reference characters relerto like -oar-ts throughout the several views. 7

and is divided into blocks by means ofthe' usual insulations 3. Tratlic is in one direction only, thatis, from right to left in Fig. l

and each block is provided with a signal and control station connected to its rails at 'its exit end, and each station is controlled by the train, it any, occupying the block of said station and one of the three blocks in advance. A signal stand at each station is provided with the usual green, yellow and red lamns, which receive current only when the block to which said station is connected, is occupied, so that there is no unnecessary When a block 18 occupied loss of current. by a train, the red lamp burns at its exit end when the next block in advance is occupied, a yellow light burns when the second block in advance is occupied, and a green light burns when the next two blocks in advance are unoccupied. The several parts of each signal installation may besa'id to be in clear, caution or danger positions when the green, yellow or red lamp respectively burns at its lamp stand 4. I j

The wires 5 andG ,connect'the track relay 7 of each block to its rails and current for the relay is conducted to the rails of each blocl; by the wires 8 and 9 from the track battery 10, the resistance 11 being employed to prevent damage to the battery when .a car axle on the rails short circuits the track relay. The relay 7 when energized holds up its armatures a, b and 0 and thereby holds open these circuits to the several signal lamps and the circuit from the battery to the train control mechanism, the common connector between the signal lamps and the current source being always closed. But when this relay 7 is de-energized by reason of its block or track section being occupied, its armatures will close the circuit to the proper lamp and to the train control mechanism so that the lamp and the train control mechanism will function. 7

Each signal installation is controlled 'by the signal installation next in advance so that if the parts of onesignal installation are in danger positions the parts of the installation next in the rear will assume to assume clear positions. No station or installation has any effect on the stations in advance.

The sections and their installations are lettered A, B, and C in Fig. 1 and these letters are occasionally associated with the numerals designating difierent parts of the installation. The armatures of the several relays will be designated by the numerals of the relays together with small letters for the armatures. Each section has battery or other current source 13 and the circuits which are employed in the signal system are shown by light lines and, those circuits which belong to the train control mechanism are shown by heavy lines. The circuits are controlled in part by a polar neutral relay llwhose winding is connected to the installation next in advance by wires 15 and 16. Current flows to this relay 1% from the stat-ion next in advance over wire 15 and back over wires 16 when clear conditions control, and flows in the opposite direction when caution conditions control, and no current flows over these wires when danger conditions control. The relay 14 has neutral armaturcs a, Z), 0 and (Z, and also has polar armaturcs e and 7.. For convenience it will be assumed that positive current flows to the relay l l of each station over the wire 15 thereto when the parts of that installation are to be at clear positions, and that this causes the armatures c and f to swing clockwise, while negative current flows over this wir 15 when the installation is to be at caution, at'which time these armatures e and 7 swing coun-t ter-clockwise. train T passed the signal station insulations 3 dividing the blocks A and B, so that the polar armat-ures c and f of relay 14L of station B are still in the positions they as sumed when positive current came to this relay 1% over the wire 15. But when the train entered. this block A, relay 7 of block A was short circuited and therefor no current flowed over wire 15 to station E. It

I if,

' there were a train in block B, current would 26 to polar armature 14 wire 25, armature flow from battery 13 to the lamp stand, relay 7 then being tie-energized. he circuit is from the battery 13 over wire 17 to the lamp R and back over wire 18, armature 14;, wire 19, armature 7, wires 20 and 21 to the battery. It will be noticed that armature 14 is in its lower position because the .relay 14 is deenergized on account of receiving no current from the battery of the station ahead.

If the two blocks in advance of block B were unoccupied and a train entered block B, current would flow from battery 13 over wire 17 tothe green lamp, thence over wire 14:, wire 19, armature 7 and wires 20 and 21 to the battery.

Block A was clear until the and the eaaeso At station C, block C being occupied, current flows from the battery over wire 17 to yellow lamp Y, and over wire 24;, polar armature ll wire 25, armature 1 1 wire 19, armature 7 and wires 20 and 21 to the battery.

The circuits to relays 14 are as follows: beginning with the negative of battery, 13 then over wire17, armature 1r, wire 22, armature 7 wire 23, armature Z) of relay 62 (which will be explained later on) and wire 15 to relay 14 thence over wire 16 armature 14 of station E, and wires 20 and 21 to the battery. This causes armatures 14: and 14 to swing counter-clockwise. The current is described as always flowing to each relay 141 over wire 15, and may be either positive or negative.

If block C were unoccupied and relay 7 energized, current would flow from the positive or battery 13 over wires 21 and 20, relay 1r:- wire 22, armature 7, wire 23, armature 62" and wire 15 to relay lat of the next station in the rear. But because block G is occupied, this circuit is opened by armature 7 and no current passes to relay 14 of that station.

Therefore when positive current flows over a wire 15 to a relay 1 1 of an occupied block the green lamp at the exit end of that block becomes visible. When negative current flows over this wire to a relay 14, the adjacent yellow lamp becomes visible, and when no current flows over this wire 15, a red lamp becomes visible.

The high-frequency current of predetermined wave length is propagated in the section at whose eXitend ared lamp receives current and also in the section at whose exit end a yellow lamp receives current, and the length or track which carries a vsutlicient amount of this current to affect instrumentalities installed on the locomotive or other vehicle traveling along the track will depend upon the wave length and upon the volume oi? current impressed upon the rails. One form of transforming and transmitting device is diagramunit-ically shown Fig. 4-, and the circles 34 in Fig. 1 indicate such transforming and transmitting devices. Current is conductedto suchtransmitting deviceI only when either of the two blocks in advance is occupied, thatis, when negative current passes to the rela I l from the station in advance or when no current passes to this relay, and it furthermore occurs only when the block belonging to that transmitter is occupied, and therefore when no current passes to the relay 7 of that block.

Our transformer embodies a motor generator 36 and the wires 27 and 29 connect thereto and to the filament 37 of the vacuum tube 88, an adjustable resistance 39 being provided in the filament circuit to control temperature. The wire 27 also carries highvoltage current from the motor generator to the grid coil 40 to which it connects by means of the wire 41, and the condenser 43 and the grid leak 44 connect this coil 40 to the grid 42.

The circuit to the plate 45 consists of the wire 46, plate coil 47, and. wire 48, and this coil is shunted by the variable condenser 50 whereby the oscillations may be limited to a predetermined wave length, and these oscillations are transmitted to the wires 30 and 33 through the output coil 52, this current output being materially increased upon the near approach of a vehicle whose axle short circuits the track and builds up a strong magnetic flux in the transformer-relay 70, suflicient to cause it to attract its armature a.

If block B were occupied, current would flow'froni the battery over wires 21 and 20,

armature 14*, Wire 28, armature 7, wire29 to the transformer 34, wire 27 and67 to the battery. This circuit is always closed when the block to which the installation belongs is occupied and the block next in advance is also occupied, that is, whenever no current is received over the wires 15 and 16.

When the parts are as shown at station E, the relay7 being energized, the circuit between armature 7 and wire 29 is broken so that the transformer-34 receives no current. When the parts are as shown at station C,

the relay 14 being energized and relay 7 deenergized, current flows from the battery over wires 21 and 20, armature 14, wire 28, relay 7 wire 29, transformer 84, and wires 27 and 67 to the battery. If the armatures 14 and 14 had been in their clockwise or clear positions, no connection would have been made with the wire 20 by either armature 14 or 14*.

The transmitter output coil 52 connects to a condenser 54 by means' of the wire 33 and then to the rail 2 through wires 74 and 6. This condenser prevents the passage of direct currents. The wire 30 connects to the relay and wires 7 3 and 5 connect this relay to the rail 1. Whenever the relay 70 is energized by the current from the loading coil 52, it attracts its armature a, closing the circuit to the slowrelease relay 62 over wires 77, 78 and 67. Therefore, so long as this transformer functions properly while its block is occupied, the circuit to relay 14 of the block to the rear is closed at armature 62 closes the circuit over wires 67, relay 62, wire 78, armature 62, wire 80, armature 7 and wires 20 and 21. As soon as the block is occupied, this last circuit is opened by armature 7 but if the transmitter functions properly, then the first named circuit is closed. But if the transmitter fails to tune tion, the circuit to relay 62 will open and no current will then How to relay 14 of the The armature 62 being attracted, it

next station in the rear, resulting in a clan ger'lamp showing at that station "and the circuit being closed to the transmitter of that block.

The locomotioe installation.

The locomotive installation is shown in. Figs. 2 and 3 in two positions, in the former in inoperative and in the latter in operative position. The collector coil 100 is mounted at the front end of the vehicle just in front of the leading axle and inclined to the vertical. so as to cut the lines of magnetic flux between the rails and the circuit of this coil is tuned to the current intherails by means of the adjustable condenser 101. The highfrequency oscillating current is converted by the thermo-couple orjunction 102 of any desired type, which connects to the windings of the relay 103 by means ofwires 104 and held inoperative, but when the solenoid is de-energized, the control mechanism causes the operation. of the brakes. A battery 116 supplies current for the various operations and normally, current flows from the battery over wire 117, armature Z) of relay 118, and wire 114 to the solenoid, and then back over wires 115 and 119. Relay 118 is energized by current over wire 117, arma ture 118*, wire 121, and then back over wire 122, resistance 123 and wires 115 and 119.

l vhen one of the collector coils picks up suliicient current to cause relay 103 to swing its armature a, a short circuit over wires 117 and 124, armature 103 wires 125 and 122, resistance 123, and wires 115 and 119 is established and the armatures assume the positions shown in Fig. 8. Current now flows from the battery over wire 117, armature 118, wire 127 to signal lamp 128 and over wire 119 to the battery. At this time the solenoid is de-energized and the brakes begin to go on.

Two forestalling keys 129 and 130 are provided so that the engineer and fireman, by simultaneously depressing these keys, may prevent this application by closing the new circuit to relay 118 over wires 117 and 132, key 130, wire 183, key 129 and wires 134 and 121 to the relay. The re-energized relay picks up its armatures and closes the circuit to the solenoid which immediately closes'the valve 122.

.be applied within a few seconds, dependin The brake mechanism shown in the drawings connects to the train pipe 140 and serves to relieve the air pressure therein and thus causes application of the brakes. An engineers brake valve 141 connects to the upper end of this pipe in the usual manner. The check valve 142 is normally held in the position shown .in Fig. 2 by the piston 143, slidable in cylinder 144, and the piston rod 145 connected thereto. Pressure underneath this piston is received from pipe 146 which connects to the electro-pneumatic valve body 112, the valve being held open by the solenoid 113. This valve body connects to the main pressure tank of the air-brake system by means of a pipe 147 hen the solenoid becomes deenergizcd, the pressure below the piston 143 soon becomes dispelled be cause 01 leakage, and the piston and valve 142 move to the position shown in Fi 3, when the valve 142 prevents recharging of the trainpipe through the engineers valve, but it does not prevent the engineer from applying the brakes.

When the valve 148 is seated to cut oil flow of air to the pipe 146, it opens a passage from the pipe 147 to the pipe 149 of the whistle 150 which sounds innnediately at'ter the lamp 128 indicates the presence of higlnfrequency current in the rails oc cupied by the locomotive and this sounding of the whistle indicates that the. brakes will b upon the control openings to be hereafter described.

A chamber 152 is formed in the valve body 153, and in it are slidable a slide valve 154 and a piston 155. A cylinder 156 connected to the valve body contains a piston 157 which is normally held against the head 158 by air pressure carried to the cylinder 156 by means of the pipe 159; The piston rod 160 connects the two pistons and slide valve.

In the valve body is a piston 162 connectto a stem which terminates in valve 163 which normally closes the passage to the discharge opening 164. A passage 165 in this body connects the branch 166 or the train pipe 140 to the space below'piston 162. A passage 167 connects the passage 165 to the interior oi" the valve chamber and a port 168 in the slide valve 154 permits air to pass freely to the space 18?) above the piston 1G2 and to the reserve tank 170, which results in the same pressure below and above the piston 162 and in this tank 170. As the piston 157 has a slightly greater area than piston 155, and as 'the pressure in the pipe 146 is usually-slightly greater than in the train pipe 140, the parts will normally be in the positions shown in Fig. 2.

iVhen pressure in pipes 146 and 159 is relieved, the parts take the positions shown in Fig. 3, the pressure on the piston 155 serving to press it against partition 158.

Any pressure which may have accumulated between the piston 1 55 and this partition can escape through a'groove 172 inthe piston rod 160 until the piston presses against the partition 158. .Air now flows from the space 169, through by-pass 17 3 in valve 154,

through passage 174, and out through the pressure.

7 As soon as the piston 162 is lifted by the greater pressure beneath it, this pressure escapes through the opening 164 and this reduction of pressure 1s slowly distributed throughout the train-pipe and its connections, and the brakes respond thereto. But

this reduction of pressure is immediately halted by the solenoid lifting the valve 148. lVhile the pressure in pipes 146 and 159 and in cylinders 144 and 156' dissipates very quickly through leakage, it may be found desirable to ensure this reduction by means of a permanent leak, consisting or" a plug 177 connected at any desired point and having a minute discharge opening 178, which permanently drains the main. pressure tank but is so small that the effect is practically negligible. mine how long after the lamp 128 indicates the picking-up of thetrack current, the brakes will be applied.

Vi e claim:

1. In an air brake control device,a trainpipe and a control valve therefor, a cylin der and piston" therein, a check valve adapted to prevent the flow of air from the controlwalve to the train-pipe, said check valve being normally held ol'l' its seat by said pi on, a pipe connecting said cylinder to a source of air unc er pressure, and an eloetro-pneuniatic valve to close said connection. V

2. In an air brake control device adapted o be connected to the train-pipe o'f a v hicle, a cylinder connected to the train-pipe and a piston in said cylinder, a valve connected to the piston and normally closing apassage adapted to relieve the train-pipe pressure, said cylinder beingtormed to provide equal air pressure in both sides of the piston, a slide valve and passages controlled thereby to relieve theair pressure on one side of the piston so that the pressure on the other side may move the piston to cause the valve connected thereto to open a pas sage to relieve the train-pipe pressure, and an electro-pneumatic valve to control said slide valve.

In an air brake control device adapted to be connected to the train-pipe of a ve-. hicle, a cylinder connected to'the train-pipe Its size will deter and a piston in said cylinder, a valve connected to the piston and normally closing a passage adapted to relieve the train-pipe pressure, said cylinder being formed to provide equal air pressure on both sides of the piston to keep said passage closed, a slide valve to relieve the air pressure'on one side of the piston so that the pressure on the other side may move the piston to cause the valve connected thereto to open said passage, a piston connected to said slide valve, a cylinder for the piston, a pipe connected to said piston and a source of air under pressure, and an electro-pneuinatic valve connected into said pipe and controlling the flow of air therein.

4. In an air brake control device adapted to be connected to the train-pipe of a vehicle, a cylinder connected to the train-pipe and having a passage to permit the escape of air from said train-pipe, a valve connected to the lower side of the piston and normally held seated thereby to close said passage, said cylinder being formed with passages to admit train-pipe pressure to both sides or" said piston, means to slowly relieve the pressure on the upper side the piston to permit the pressure on the lower side of the valve to move the piston to unseat said valve, and an air container connected to the space above the valve to supply air to such space and thereby slow down the reduction of pressure above the valve.

5. In an air brake control device adapted to be connected to the train-pipe of a vehicle, a pressure controlled valve to relieve the air pressure in the train-pipe, a slide valve and a pressure controlled piston connected thereto to prevent the relief of said pressure, a cylinder for said piston, and an electro-pneumatic valve governing the admission of pressure to said cylinder.

6. In an air brake control device adapted to be connected to the train-pipe of a vehicle, a pressure controlled valve to relieve the air pressure in the train-pipe, a slide valve and a pressure controlled piston connected thereto to prevent thereliet of said pressure, a cylinder for said piston, and an electro-pneumatic valve governing the admission of pressure to said cylinder, a second cylinder, a piston therein connected to said slide valve, and a conduit connecting to said train-pipe and to said second cylinder whereby train-pipe pressure may move said pistons and slide valve to permit trainpipe pressure to be relieved.

7. In an air brake control device adapted to be connected to the train-pipe of a vehicle, a cylinder connected to the train-pipe and a piston therein, said cylinder being formed With a valve chamber and With a passage connecting the space on one side of the piston to the train-pipe and to the outside air, With a second passage connecting the train-pipe to the valve chamber, With a third passage connecting the valve chamber to the space in the other side of the piston, and With a fourth passage connecting the valve chamber tothe outside air, a valve connected to the piston and normally held thereby to close the first passage to the outside air, a second valve to normally close the fourth passage, a second piston to hold said second valve in normal position, acylinder for said second piston,

a conduit connecting said second cylinder to a source of air under pressure, an electro pneumatic valve to open and close said conduit, a third cylinder connected to said valve chamber, and a third piston therein connected to said second valve, and adapted to move it to connect said third and fourth passages When said conduit is closed by said electro-pneumatic valve.

THOMAS E. CLARK. CHARLES B. STONE. 

